Prior to getting married last year, I had no idea how to calculate the amount of wine, beer, and liquor needed to serve a big crowd. Turns out, there are a few great rules to follow when predicting your guests’ alcohol intake at any event. Even better? There’s no math involved! Technology has given us easy calculators that will do the predicting for us.

Keep in mind that for every event, the amount of alcohol consumed with vary based on type of event, time of year, time of day, and menu being served.

Below are two of the better drink calculators on the web (and trust me, we looked at a LOT out there). The first is from That’s the Spirit and also will let you calculate the cost of your beverages so you can better budget for your event.

The second calculator comes from Evite and lets you predict the amount of heavy, medium or light drinkers attending your event. Then, it calculates the total number of drinks needed. Once again, these tools probably aren’t spot on, but should provide a pretty good basis for your beverage order.

We saved the best for last! Meet every college frat boy’s favorite app, the KegWizard. Instead of using more polite ways of asking how drunk your friends usually get, this tool just tells it like it is. You can select how many of your friends will likely get tipsy, buzzed, drunk or hammered, and then it will “kegulate” the amount of beer, ice, and red plastic cups needed for an epic event.

Note that if you’re stocking your own bar, there are six basic spirits you should have available: rum, vodka, gin, tequila, whisky and a scotch or Bourbon. The most common mixers to buy for these spirits are club soda, tonic, cola, diet cola, ginger ale, lemon lime, orange juice and cranberry juice. Also make sure to have plenty of limes on hand. Unfortunately none of the drink calculators we saw also accounted for mixers or fresh fruits. Perhaps this is a new opportunity for someone out there to create a new app! Any takers?

Have you ever used an online drink calculator for one of your events? How accurate was it for you? We’d love to hear how you fared! Leave us a note in the comments below or find us on Twitter.